Pneumatic-despatch-tube apparatus.



C. S. JENNINGS.

PNEUMATIC DESPATCH TUBE APPARATUS.

APPLICATION FILED IULYII, 1907.

a I I'I messes -ZWGGQM/ Patented Apr. 27, 1915.

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mitted between stations.

CHESTER s. JENNINGS,. or, assets, mssacnusn'rrs, AssIGNon, BY NmsNEASSIGN- MENTS, T0 AMERICAN PNEUMATIC snnvros GOMLPANY, or BOSTON,MASSACHU- SETTS, A. CORPORATION OEIDELAWABE.

PNEUMATIO-DESPATCH-TUBE AP?ARATUS.

To all whom it may concern:

Be it known that I, CHESTER S. JENNINGS, a citizen of the United States,residing at Boston, in the county. of Sufiolk and State ofMassachusetts, have invented certain new and useful Improvements inPneumatic- Despatch-Tube Apparatus; and I dohereby declare the followingto be a full, clear, and exact description of the invention, such aswill enable othersskilled in the art to which it appertains to make anduse the same. 1

The invention relates to pneumatic despatch tube apparatus, and moreespecially to mechanism controlling the passage of air through thesystem in such manner that air passes only when carrlers are beingtrans- The primary object of the invention is to provide mechanism forcontrolling the pas- V sage of air through the transit tubing whichshall be simple in construction, and which will act in a uniform andreliable manner under the varying conditions'which arise during the useof the system.

,sists in providing transit tubing, in which tion of power.

Further features of the invention relate One of the features of theinvention conthere is a plurality of despatch stations, with an airvalve for controlling the passage of air through the tubing andoperating the valveby mechanismthe action of which is not dependent uponthe pressure in the system, and which acts to automatically open thevalve when a carrier is despatched from any station, andto automaticallyclose the valve after suflicient time has elapsed. for the carrier to betransmitted to its destina tion. iThe valve is thus open only when acarrier is to be transmitted fromone or all of the stations, and theperiod during which the valve remains open may be reduced to a minimumsince the action of the controlling mechanism is unaflected byvariations in the pressure in the system such as may be caused by anincrease in the number ofcarriers in transit at the same time.Consequently the mechanism which produces the flow of air through the,system may act in a highly efiicient manner and with a minimum consump-1 v be understoodfrom an inspection of the ac- Patented Apr. 2'3, 1915.

Application filed. July 11, 1907. Serial No. 383,176.

companying drawings in which Figure l is an elevation showingdiagrammatically an apparatus embodying the invention, and 2 is asectional detail showing the air valve and controlling mechanism.

In the apparatus illustrated in the drawings the transit tube A fortransmitting carriers from a central station to a sub-station isprovided with an open bell-mouth so that the carrier may be readilyintroduced into the tube by the cashier or other person at the centralstation. This tube leads to the terminal C at the sub-station, which isof the usual construction, and is provided with a suitable valve 0 forclosing the opening through which the carrier is discharged. Thetransmission tube B for transmitting the carriers from the sub-stationto the central station is connected with the terminal 0 in the usualmanner, and is provided with a carrier inlet opening which is normallyclosed by the usual valve or door E. The de-' livery end of the transittube -B is connected with a terminal D which is provided with a carrierdischarge opening through which the carrier is delivered at the centralstation. This opening is'normally closed by a door or valve d'of usualconstruction; The means for causing air to flow, through the transittubing comprises avacuumior suction drum F, which communicates with theterminal D through tubes G G and a valve casing H introduced betweensaid tubes. The valve casing is divided horizontally into two chambers71. k by a partition H, and the pipes G G communicaterespectively withthe chambersh M. An opening k is formed through thepartition H and thecommunication between the chambers 72. k is controlled by means of an*air valve I; When the valve is closed there is no communication betweenthe transit tubing and the suction or vacuum drum F, and there is nopassage of air through the transit tubing. When the valve I is openedthe transit tubing is connected through the pipes G valve casing H, andpipe G with the suction drum, and air passes through the transit tubinguntil the valve is closed.

The air valve is held normally closed by a spring J the tension of whichmay be Varied to'suit the conditions under which the an paratus isoperating by means of a nut K against which the upper end of the springbears. The mechanism for opening the valve comprises a solenoid L, thearmature L of which is connected with a valve operating lever M. Thelever M is connected with the rod I on which the valve I is secured bymeans of a pin andslot connection The solenoid L is energized to openthe air valve whenever a carrier is introduced into the transit tubingat any of the stations therein. For this purpose circuit closing devicesare provided at each station, which are operated to open and close thesolenoid circuit when a carrier is introduced into the transit tubing.

' The circuit closing devices for the central station comprise contactsN which are included in the solenoid circuit. A switch arm N is arrangedat the mouth of the tube A and is provided with a contact piece Narrangedto engage the contacts N and close the solenoid circuit. Theswitch lever is held normally with the contact arm N out of engagementwith the contacts N, so that the solenoid circuit is normallyopen atthis point. "lVhen a carrier is introduced into the mouthof the tube Ait swings the switch lever N so as to engage the contact arm N with thecontacts N and close the solenoid circuit. The solenoid is thusenergized and acts to open the air valve so that a suction is created inthe transit tubing which causes I the carrier to travel through thetubing. As soon as the carrier passes the switch lever N.

the lever returns to normal position, thus.

breaking the solenoid circuit and deenergizing the solenoid so that theair valve is released and may close under the influence of the spring Iand the controlling mechanism to be described.

'The circuit closing and opening devices for the sub-station are,similar to the devices I just described, and consist of contacts N inthe solenoid circuit which are arranged to be engaged by a contactarmNtconnected with the door E which closes the'carrier receivingopening in the'tube B. When the door 12 is open to insert a carrier thesolenoid circuit is closed and the air valve opened. When the door isclosed after introducing a carrier into the transit tubing, the solenoidcircuit is broken atthis point and the valve is free toclose under theinfluence of the spring J and controlling mechanism.

The means for controlling the closingof the valve so that it may remainopen during the time required to transmit the carrier from one stationto another comprises a controllingchamber 0 formed within the easingH:and provided with a movable wall 0 which is connected with a downwardlyprojecting extension I of the valve rod'I. The movable wall of thecontrolling chamber is preferably in the form of a flexible diatheopposite'wall of the chamber to accomphragm which may move toward andfrom freely through the air inlet but passage of air in the oppositedirection is prevented. In the construction shown the check valve is inthe form of a small ball mounted in a valve chamber formed in the airinlet. The controlling chamber is also provided with a restricted outletor vent 0 through which the air within the chamber may escape during theclosing of the valve I. The flow of air through this vent may beregulated by means of an adjustable valve or screw 0 .VVhen the airvalve I is open the diaphragm O is moved upward and during this upwardmovement of the diaphragm air is freely admitted to the controllingchamber 0 through the airinlet 0 and check valve 0". When the solenoidis deenergized, and the valve is released the closing of the valve isopposed by the air within-the regulating chamber 0 and the time duringwhich the from one station to anotherin the transit.

tubing. V

While I have shown'the-invention embodied in an apparatus in which theair valve is arranged between the transit tubi'ng and the means forproducing'a .flow ofair through the tubing, since certain featuresof'the'invention relate more particularly to such an apparatus, it willbe understood that so far as certain other features of the invention arelating more or less to the specific form of valve'controlling devices,the invention may be embodied in systems in which the air valveisotherwise located, andin. which a part or all of the transit tubing isin constant communication with the suction drum or other 'means forcausing air to flow through the tubing. 7 V T Having set forth thenature and object of theinvention, and describedone form of apparatus inwhich it may be embodied, what I claim is 1. In pneumatic despatch tubeapparatus,

a transit tube for the transmission of carriers, an air-exhaust pipecommunicating V'- with said transit tube, a casing interposed twochambers," a spring normallyiclosing valve controlling saidiopeningbetween the 'in the communication between the transit 105 j concerned,and'especially those features rei said valve, a lever pivoted on theexterior of the casing and connected with said valve, a solenoid havingits armature connected with the free end of saidlever; an electriccircuit including said solenoid, a normally open switch actuated by theinsertion of a carrier in the transit tube to momentarily close theelectric circuit to energize the solenoid so that the movement of itsarmature through the intervening mechanism will open said valve topermit the flow of air through said chambers from the transit tube tothe exhaust pipe, a diaphragm connected with said valve positioned inthe casing chamber communicating withthe exhaust pipe and forming withthe wall of such chamber a controlling chamber, said controlling chamberhaving an air inlet to admit outside air when the diaphragm risesthrough the opening of said valve by the solenoid and said controllingchamber having a restricted vent to permit the egress of air when thediaphragm lowers through the closing of the valve by said spring, acheck-valve to prevent the egress of air through said airinlet of thecontrolling chamber, and a screw-valve to regulate the egress of air Ythrough said. restricted vent of the controlling chamber to retardtheclosing ofsaid Valve through the action of the spring.

2. A pneumatic 'despatchtube system, having, in combination, transittubing through which carriers are transmitted, an

air valve for controlling the 'passage -of air through said tubing,mechanism operating independently of variations in pneumatic pressure toopen the valve upon thedespatch ing of a carrier," and timing mechanismact ing to control the closing of the valve, said valve having a casingwith a, chamber therein which when said valve is closed is normally incommunication with said transit tubing and with said tubing alone.

3. A pneumatic despatch tube system, having, in combination, transittubing through which carriers are transmitted, means for exhausting airfrom said tubing, an air valve between the transit tubing and saidmeans, electrically operated mechanism connected to open. the valve,means for making and breaking the circuit for said mechanism whendespatching the carrier, and a timing mechanism for automatically timingthe closing of said valve, said valve when being closed, timed by saidtiming mechanism, and when open even but partly, affording communicationbetween said air exhausting means and said transit tubing alone.

l. A pneumatic despatch tube system, having, in combination, transittubing through which carriers are transmitted, an air valve forcontrolling the passage of air through said tubing, an exhaust device,means operating independently of the exhaust device for opening thevalve upon the despatch of a carrier and a timing mechanism forautomatically controlling the closing of'the valve, said valve whenbeing closed, being timed by said timing mechanism, and when open evenbut partly, afford ng communlcatlon between said a1r exhausting I meansand said transit tubing alone. p

In testlmony whereof I. aflix my signature, 1n presence of twowltnesses.

CHESTER S. JENNINGS. Witnesses:

IRA L. FIsH, N. D. MCPHAIL.

' Copies of this patent may be' obtained forfive cents each, byaddressing the G'ommissioner of Patents.

Washington, D. C.

